Process for manufacturing flock

ABSTRACT

A tow of textile material is scoured and rinsed to remove its original finish. The tow in a wet condition is directed to a cutter which cuts the tow into fibers of desired length. The fibers are separated from one another and are dried prior to collection. A new finish is applied to the material at an appropriate point in the process subsequent to removal of the original finish and in advance of collection.

United States Patent 11 1 Hagborg PROCESS FOR MANUFACTURING FLOCK [75] Inventor: Winston E. Hagborg, Columbus, Ga.

[73] Assignee: West Point Pepperell, Inc., West Point, Ga.

221 Filed: Jan. 29, 1974 21 Appl. No.: 437,617

[52] US. Cl. 427/185; 118/36; 118/73; 427/290 [51] Int. Cl. B44D 1/18; CO3C 25/02 [58] Field of Search 117/4, 47 A, 100 A, 100 C; 118/36, 73; 427/185, 290

[56] References Cited UNITED STATES PATENTS 3,490,938 1/1970 Hoover et a1. 117/4 X Oct. 28, 1975 3,714,136 l/1973 Gershberg 117/100 X Piimary Examiner-Michael R. Lusignan Attorney, Agent, or Firm-Cushman, Darby & Cushman [57] ABSTRACT A tow of textile material is scoured and rinsed to remove its original finish. The tow in a wet condition is directed to a cutter which cuts the tow into fibers of desired length. The fibers are separated from one another and are dried prior to collection. A new finish is applied to the material at an appropriate point in the process subsequent to removal of the original finish and in advance of collection.

1 Claim, 6 Drawing Figures US. Patent I Oct.28, 1975 Sheet 1 of4 3,916,040

\. QQQSW U.S. Patent Oct. 28, 1975 Sheet2of4 3,916,040

Oct. 28, 1975 Sheet 4 of4 3,916,040

US. Patent mm w PRUQEfiS F051 MANUlFACTUlRlNG FLOCK BAQKGROUND OF THE INVENTION The present invention relates to a process for manufacturing flock for use in textile applications. Typical uses for flock are described in US. Pat. No. 3,528,874 to Francis T. Spencer. Briefly, the Spencer patent discloses an arrangement wherein flock is deposited on an adhesive coated substrate, the adhesive securing the flock to the substrate. The resultant product is suitable for use as blankets, sleeping garments, upholstery fabrics, draperies, etc.

There are several important considerations in the manufacture of flock. One is that the flock be free of any finish which would impair its lustre, hand and abi1- ity to be deposited on the substrate. Another is that the flock be devoid of clusters or calls so as to insure uni form distribution. Still another consideration is that flock fibers should be straight rather than curled.

in known processes for preparing flock, one or more of the above-described problems are encountered due to processing techniques which cause fusion of the flock, curvature of the fibers, etc. However, the present invention constitutes an improved process for manu facturing flock which prevents curling and fusion of the flock and provides the flock with a finish which is compatible with the method by which it is deposited. Briefly, this is accomplished by passing the tow through a scouring bath to remove the finish applied to the tow material during manufacture. While in a wet state, the tow is directed through a cutter which chops the tow into fibers of the desired length. Thereafter, the fibers are dried and are placed in storage. Either prior to the cutting step or after cutting the material is subjected to a finishing operation in which suitable chemicals are applied to ready the flock for its ultimate use.

Several embodiments of the invention will be described in connection with the accompanying drawings wherein:

lFlG. l is an illustration of the scouring and finishing portions of the flock manufacturing process according to a preferred embodiment of the invention;

FIG. 2 is an illustration of the cutting, drying and storing portions of the flock manufacturing process, according to a preferred embodiment of the invention;

FlG. 3 is an enlarged view, partially fragmented, of the cycione separator shown in H6. 2;

FIG. 41 is a block diagram illustrating an alternative process for flock manufacturing according to the invention;

FIG. 5 is a block diagram of a further alternative process for flock manufacturing according to the invention; and

HG. eis a side elevational view, partially in section, illustrating equipment suitable for use in the extraction step diagrammatically shown in FIG. 5.

Referring now to the drawings, the improved process will be described. A tow of filaments, designated as 10, is drawn from a supply bin. While this tow is preferably of synthetic material, such as nylon, polyester, rayon or an acrylic, it is also contemplated that the tow may be formed of natural fibers.

The tow 11h, as it is removed from the supply bin, contains a finish imparted during its manufacture having properties which are undesirable for the intended application of the flock. Typically, these properties are cohesive and anti-static characteristics which contribute to clustering of the flock fibers and difficulty in depositing the flock when an electrostatic process is employed, such as is described in US. Pat. No. 3,528,874 Spencer. Consequently, such a deleterious finish must be removed. This is done by passing the tow 10 through a tensioning arrangement, comprising an eye 12 and conventional spreader bars 14, to a tank assembly generally indicated at 16. The spreader bars are a conventional combination of curved and straight bars which prepare the tow for the scouring operation by flattening It.

The tank assembly 16 comprises four tank sections 18, 20, 22 and 24. Each of the sections is provided with a conventional multiple roller arrangement to permit several changes in direction of the two as it passes through the section. Additionally, a drive roller 26 is provided at the output end of each tank section to draw the tow therethrough. A guide roller 28 is positioned at the input end of tank 18. An assembly of squeeze rollers 30 is mounted on a suitable framework 32 to permit the rollers 30 to be selectively withdrawn from corresponding rollers 26 or advanced into cooperative relationship therewith. After threading the tow 10 through eye 12 and spreader bars 14, over the guide roller 28, and around drive rollers 26 and the multiple rollers within the several tank sections, the squeeze rollers 30 are dropped to engage the tow thereby permitting the drive rollers 26 to carry the tow through the several tank sections 18, 20, 22 and 24 and deposit it in a receptacle 34.

As the tow 10 passes through tank section 18, a scouring operation occurs. Typically, the scouring agent is a combination of soap, a suitable solvent and soda ash maintained at an elevated temperature of approximately lF. After passing from section 18, the tow moves to tank section 20 where it is exposed to a first rinse, and from tank 20 the tow passes to tank section 22 for further rinsing. While only two rinses are disclosed, it will be understood that any number is appropriate provided the original finish and the scouring agent is removed from the tow by the time it exits from the last rinse. The details of the rinse operation need not be presented here inasmuch as they are well known. However, it should be mentioned that the temperature of the rinses correspond substantially to that of the scouring bath.

On exiting from tank section 22, the tow 10 passes into tank 24 where a new finish is applied to the tow. This finish is of a character which enhances the ability of the tow material, when chopped into flock fibers,to flow or sift. In other words, the finish is one which minimizes the tendency of the flock to cluster. Additionally, the finish is made compatible with the adhesive which is ultimately utilized in securing the flock to a substrate. If the flock is to be electrostatically deposited, the electrical properties of the finish are selected to facilitate such a step. A typical finish agent having the foregoing properties consists of Leomin KP Type F and waterglass. Leomin KP Type F is a quaternary fatty acid derivative marketed by the American l-loechst Corporation located in Mt. Holly, North Carolina and being a subsidiary of Farbwerke l-loechst AG of Frankfurt, Germany. It is a cationactive preparation, which is slightly alkaline in an aqueous solution. It is resistant to acid and alkali concentrations, is soluble in hot water, and has good resistance to hard water and frost.

As is the case during scouring and rinsing, during the finishing operation, the temperature of the bath is elevated. Typically, this temperature is in the order of 140 F. The arrangement is such that the collected tow which is deposited in receptacle 34 is in a substantially wet state, e.g., 0.3 to 0.4 pounds liquid per pound of dry tow.

Referring to FIG. 2, additional steps of the process will be described. A plurality of receptacles 34 (not shown in FIG. 2), each filled with a wet tow 10, are arranged adjacent a conventional creel assembly 36 only one stage of which is shown. The combined tows from the several receptacles 34 are directed through the creel assembly to a cutter unit 38. The unit shown is a conventional commercially available guillotine type cutter having a puller roll incorporated therein. While a guillotine type cutter is disclosed, it is apparent that other types of cutters, such as rotary ones, may be employed. Additionally, supplemental pull rolls linked to the cutters roll may be interposed between the cutter 38 and the creel assembly 36. The pull rolls move the combined tow bundle from the creel assembly 36 by indexed amounts (e.g., 2 mm) past the cutter knife. Typically, cutter 38 operates at a rate of approximately 120 cuts per minute. Inasmuch as the tow is wet as it passes the knife, the latter is maintained in a cool condition so as to inhibit fusing of the flock fibers which otherwise would occur if the tow were dry so as to 'allow the knife to increase in temperature during the cutting operation.

.On exiting from the cutter 38, the flock fibers drop via a chute 40 into a duct 42 which is positioned intermediate a heater 44 and a blower 46. The direction of movement of the fibers as they enter duct 42 is approximately at right angles to the longitudinal axis of the duct. The fibers and heated air from heater 44 are pneumatically moved by blower 46 through ducts 42 and 48 to a mechanical separator, such as a conventional pin mill 50. The blower also assists in separating lumps of fibers. During passage through ducts 42 and 48, the flock is flash dried, the ducts being thermally insulated to facilitate such drying. The drying process is controlled by a thermally responsive element 52 which is positioned in duct 48 just upstream of the pin mill 50. The temperature responsive element 52 is operatively connected to a valve arrangement (not shown) positioned within duct 42 between the heater 46 and chute 40. The valve is continuously adjusted to control the temperature within the duct to a value of approximately 300 F. This reduces the moisture content of the flock fibers to a sufficient level to prevent clustering. Of course, the length of the ductwork is selected to facilitate the drying operation.

The purpose of the pin mill 50 is to assist in breaking up clusters of fibers which are formed for example by the knife in the cutter 38 dulling or developing nicks so as to cause light fusion of the flock fibers. The fibers exiting the mill 50 are directed via an additional insulated duct 53 to a conventional cyclone separator 54 which isolates the dried flock fibers from the heated air, the latter being exhausted to atmosphere.

The cyclone separator 54 is shown partially fragmented in FIG. 3. It can be seen that as the heated air carrying the flock fibers enters the separator, it swirls in the chambers within the separator established between the inner cylindrical wall 56 and the separators outer wall. Centrifugal force separates the heavier flock fibers from the air stream, the conical base 58 below cylinder 56 facilitating the direction of the air upwardly to be exhausted to atmosphere while the dried fibers drop through a funnel 60 to a collection drum 62 (FIG. 2).

While the arrangement just described constitutes a preferred embodiment of the invention, variations in the process can be made without departing from the inventive concept. One such variation is illustrated in FIG. 4. In this embodiment, the finishing step between scouring and placing the wet tow through the creel is eliminated in favor of a finishing procedure subsequent to the dried flock fibers being passed through the pin mill. In the modified operation, the fibers are dried completely in the flash drying step, and as the fibers pass through duct 53, a conventional nozzle arrangement introduces a fine mist of finishing materials of the type previously described to the air stream to coat the fibers. By suitable adjustment of the nozzle, the moisture content of the resultant flock can be controlled to acceptable limits.

The embodiment of FIG. 5 again eliminates the finishing step between the scouring and cutting steps. After the wet tow is cut, it is combined with a liquid to form a slurry. By moderately high shear mixing of the slurry, the flock fibers are suspended in unclustered condition in the liquid permitting suitable finishing materials to be added to the slurry so as to coat the fibers. The slurry is next directed to screening devices to drain the bulk of the liquid from the mixture. The remaining wet mass of fibers is then introduced to conventional dewatering apparatus, such as a pressure or centrifugal extractor, or to continuously operating equipment such as that disclosed in FIG. 6. If the latter is employed, the wet mass is placed in the hopper and is carried by a motor driven auger 64 from a feed section to a compression chamber 66 which separates additional liquid from the fibers. The moist fibers then are carried through a metering section by the auger and are introduced to a duct 42' corresponding to duct 42 in the embodiment of FIG. 2. Duct 42' is connected between a heater and a blower in a manner similar to the FIG. 2 arrangement so as to flash dry the fibers to a desired moisture level. The dried fibe'rs are subsequently directed to a cyclone separator to be processed as previously described.

The descriptions of the several embodiments disclose a variety of processes for fabricating flock which is free from fusion and curling and which has an acceptable finish. Variations of the disclosed processes also are possible and are intended to be covered by the following claims.

What is claimed is:

l. A process of manufacturing flock from a tow of textile material comprising the steps of:

scouring and rinsing said tow; 1

cutting the tow while in a wet state into fibers of desired length;

applying a selected finishing agent to the material by combining said fibers, a liquid and said agent in a slurry and then extracting excess liquid and finishing agent from the slurry; and

transporting the fibers pneumatically at an elevated temperature past a blower so as to dry and separate the fibers for collection. 

1. A PROCESS OF MANUFACTURING FLOCK FROM A TOW OF TEXTILE MATERIAL COMPRISING THE STEPS OF: SCOURING AND RINSING SAID TOW, CUTTING THE TOW WHILE IN A WET SLATE INTO FIBERS OF DESIRED LENGTH, APPLYING A SELECTED FINISHING AGENT TO THE MATERIAL BY COMBINING SAID FIBERS, A LIQUID AND SAID AGENT IN A SLURRY AND THEN EXTRACTING EXCESS LIQUID AND FINISHING AGENT FROM THE SLURRY, AND TRANSPORTING THE FIBERS PNEUMATICALLY AT AN ELEVATED TEMPERATURE PAST A BLOWER SO AS TO DRY AND SEPARATE THE FIBERS FOR COLLECTION. 